Showing papers on "Four-stroke engine published in 1998"

Free-piston internal combustion engine

Abstract: An efficient free-piston internal-combustion engine (802, 811, 832, 14, 114, 314, 614) having an expansion ratio greater than the compression ratio. The engine has a gas bearing (804, 813, 831) and an exhaust temperature in excess of 600 °C which are used to operate as a topping cycle for gas turbines, Stirling engines, steam engines, etc. An improved valving system for flexible control of the engine may include the use of a valve actuator (28, 32, 132, 410, 616) in a piston. In one embodiment, a pair of oppositely disposed combustion chamber passageways each have a combustion-chamber valve (132, 410) for controlling the passage of gas through the passageways. Variable control of the piston positions at which the valves are opened and closed permits the engine to operate at a high efficiency over a broad range of power output loading conditions. In another embodiment the combustion chamber and a gas compressor are combined in the same cylinder.

In-cylinder direct-injection spark-ignition engine

Abstract: A direct-injection spark-ignition engine operable between a stratified charge combustion mode where fuel injection is executed on a compression stroke while introducing a vertical-vortex tumble flow to an induced air drawn into a combustion chamber through an intake port, and a homogeneous combustion mode where fuel-injection early in the intake stroke produces a homogeneous air-fuel mixture, comprises a cylinder block having a cylinder, a piston movable through a stroke in the cylinder and having a centrally-formed piston bowl cavity combustion chamber in its piston head, a cylinder head mounted on the cylinder block, a centrally-located spark plug, and a fuel injector valve provided nearby the intake valve for injecting fuel directly into the combustion chamber. The piston bowl cavity combustion chamber is formed, so that the deepest portion of the piston bowl cavity combustion chamber is obtained at the center of the piston head, and the inner peripheral concave wall surface of the cavity combustion chamber is contoured to be curved in a direction of a streamline of the vertical-vortex tumble flow.

Two-stroke diesel engine

Abstract: A two-stroke, opposed piston, diesel engine is provided herein. The engine includes a thermal shield and a fluid gap which surround the exhaust ports to shield the engine block from an exhaust fluid from the cylinder assembly. Additionally, a cooling fluid is transferred to a plurality of helical shaped passageways which encircles the cylinder housing. These features allow the engine to operate at a cooler temperature and allow for more uniform cooling of the engine. Preferably, the engine also includes a first injector which injects a combustion fluid into the cylinder chamber between the pistons in the same direction as a swirl created within the cylinder chamber. This increases the distribution of the combustion fluid in the cylinder chamber and enhances the efficiency of the engine.

Engine system employing an unsymmetrical cycle

Abstract: Highly efficient engine. The system includes an internal combustion engine having at least one piston in a cylinder, the cylinder including a cylinder head. The engine operates on an unsymmetrical expansion and compression cycle wherein the expansion portion of the cycle is greater than the compression portion of the cycle. The piston and cylinder head are lined with an insulating material having a selected thermal diffusivity. Apparatus is provided for injecting a supercritical mixture of fuel and water into the cylinder of the engine. The combination of these aspects results in a highly efficient engine.

Internal combustion engine with dry sump lubricating system

Abstract: An internal combustion engine with dry sump lubricating system includes a feed pump which supplies lubricating oil from a lubricating oil tank disposed outside an engine body to all moving parts in the engine. After circulating through the engine, the lubricating oil drops down into a crank chamber and is immediately picked up from the crank chamber and sent back into the lubricating oil tank by a recovery pump. Since the lubricating oil tank is attached to an end of the engine body from which a crankshaft project, it does not increase the overall width (dimension in the direction perpendicular to the axis of the crankshaft) and height of the engine. Even when the engine has inclined cylinders, the lubricating oil tank can avail a high degree of design freedom because the end face is not influenced by inclination of the cylinders as greatly as side surfaces of the engine body. The engine also includes a breather system so designed as to prevent an operation failure of the engine which would otherwise be caused due to inflow of the lubricating oil into an intake system of the engine.

Internal combustion engine with spark ignition

Abstract: A combustion chamber formed by a recess in the piston of an internal combustion engine is divided by restrictions into two or more partial chambers. The ratio between the minimum distance in the area of the restrictions and the maximum distance in concave areas of the wall of the combustion chamber, as measured from the axis of the combustion chamber, is between 0.2 and 0.5. In the area of the minimum distance downstream of the restriction, the wall of each partial chamber is inclined relative to the axis of the combustion chamber, the inclination decreasing continuously in downstream direction. To achieve extremely lean operation with low exhaust emissions, the fuel injection device is located in a position eccentric to the center of the combustion chamber, and the ignition device is located approximately in the center of the combustion chamber. The restrictions of the piston recess are provided with guide faces located approximately parallel to the axis of the combustion chamber and directed towards the center of the combustion chamber, the smallest distance of these guide faces from the center of the combustion chamber being 0-0.2 times the piston diameter.

Process for controlling self-ignition in a 4-stroke engine

Abstract: The present invention is a process for controlling self-ignition in a four-stroke engine comprising variable control of the opening and the closing of the intake and exhaust in the combustion chamber as a function of the engine load. At partial load the invention performs (a) prolonged retention of burned gases in the combustion chamber, and (b) a fresh gas intake period which overall follows the retention period, in order to minimize mixing of the fresh gases with the burned gases and to control the amount of burned gases retained in the combustion chamber.

Procedure for running of four-stroke reciprocating piston internal combustion engine

Abstract: In a firing phase the held-back exhaust gas is compressed in the domain of the gas exchange dead center and then expanded. In this phase of the working cycle the firing fuel is injected into the combustion chamber (3) for stabilizing the primary combustion. A control circuit by consideration of the inadvertent RPM and load fluctuations of the engine stabilizes the primary combustion through quantity and injection times of the firing fuel.

Dual fuel engine which creates a substantially homogeneous mixture of gaseous fuel, air, and pilot fuel during a compression stroke

Abstract: A method of operating an engine assembly having a cylinder assembly which defines a combustion chamber is disclosed The cylinder assembly includes an engine block having a piston cylinder defined therein, a piston which translates in the piston cylinder, and a crankshaft which is mechanically coupled to the piston The method includes the steps of performing an intake stroke of the engine assembly and advancing gaseous fuel and air into the combustion chamber during the intake stroke performing step The method further includes the step of performing a compression stroke of the engine assembly after the is intake stroke performing step The method yet further includes the step of injecting a pilot fuel into the combustion chamber during the compression stroke while the crankshaft is positioned at about X degrees before top dead center, wherein 210

Electric motor driven primary oil pump for an internal combustion engine

Abstract: A primary pump system for lubricating an internal combustion engine includes a pump constructed and arranged to pump lubricant to an engine prior to engine cranking and continuously during operation of the engine. A variable speed electric motor is constructed and arranged to drive the pump independently of engine speed. A controller controls operation of the motor and thus the operation of the pump. An engine load sensor senses a load on the engine. The controller is responsive to a signal received from the engine load sensor to control the motor so that the pump may supply lubricant to the engine in accordance with engine load.

Internal combustion engine having deceleration fuel shut off and camshaft controlled charge trapping

Abstract: A reciprocating internal combustion engine using poppet valves, valve timing control and fuel injection, cuts off fuel during engine deceleration and controls valve timing such that charge is trapped in the engine cylinders while the fuel is shut off.

Four-stroke internal combustion engine with recuperator in cylinder head

Abstract: A recuperating four-stroke internal combustion engine obtains improves Carnot efficiency by use of a new and novel cylinder head which captures thermal energy normally thrown away in the exhaust and re-introduces it to the working cycle. This result, long sought by others, has been achieved by incorporating within the head a compact internal recuperative heat exchanger in series with a combustion chamber or pre-chamber. A recuperator-protecting valve segregates the recuperator from hot combustion gases until the gases reach maximum expansion in the cylinder. Recuperators of both common-duct and seperated-duct design are described, the separated duct recuperator permitting higher recuperator temperature and increased efficiency and a reduction in the number of valves necessary to control gas flow. A preferred embodiment employs four valves per cylinder unit, a separated duct recuperator, and an insulating liner that surrounds both the combustion chamber and the recuperator. A similar prototype recuperative engine has demonstrated that recuperation can reduce exhaust temperature as much as 600° Rankine below that attainable in an equivalent Otto Cycle engine.

Overhead cam engine with integral head

Abstract: A single cylinder, internal combustion engine with a dry sump lubrication system. The engine includes an engine housing in which the overhead camshaft and crankshaft are rotatably supported, and the housing includes an integrally formed cylinder and head. A timing belt disposed externally of the engine housing interconnects the crankshaft and camshaft, and a piston connected to the crankshaft reciprocates within an internal bore provided in the engine housing cylinder. The cylinder wall around the internal bore is of a generally uniform thickness and circumscribed by cooling fins such that the cylinder resists bore distortion during operation. Dry sump lubrication is obtained by an external oil reservoir connected to a pump which supplies pressurized oil to the bearing journals of the camshaft. A portion of the oil at the camshaft bearing journals flows through passages provided within the cylinder to lubricate the bearing journals of the crankshaft. The reciprocating motion of the valve assemblies controlling intake and exhaust of the combustion chamber pumps the oil which lubricated the camshaft back to the external reservoir. The reciprocating motion of the piston similarly effects a high pressure within the crankcase cavity to pump oil which has lubricated the crankshaft back to the external reservoir. The inventive engine further provides for the mounting of flywheels within the crankcase cavity in conjunction with an external, lightweight fan for engine housing cooling, as well as employs a cast in valve seat for the overhead valve assemblies.

Engine front cover

Abstract: An internal combustion engine is described having a crankshaft (14) and a camshaft, the ends of which project from a front end of the engine. A hydraulically operable variable valve actuation mechanism is mounted on the camshaft at the front end of the engine for driving the camshaft. A front cover (10) that overlies the end of the camshaft projecting from the front end of the engine, includes passages (40, 42) that are connected to supply oil under pressure from an engine driven pump (16) to the variable valve actuation mechanism.

Internal combustion engine with variable camshaft timing and intake valve masking

Abstract: A reciprocating internal combustion engine has a pilot mask situated about the intake valve seat and extending into the engine cylinder and a variable camshaft timing drive system which positions the camshaft such that the lift of the intake valve and the height of the pilot mask are approximately equal when the piston is moving at the point of its greatest velocity during the intake stroke.

Method for starting an internal combustion engine in a motor vehicle

Abstract: A method is provided for starting an internal combustion engine for a motor vehicle, and an internal combustion engine is provided which employs such method. The internal combustion engine includes a piston which can move in a cylinder and can execute an intake stroke, a compression stroke, a power stroke and an exhaust stroke. In addition, a control unit is provided with which fuel can be injected directly into a combustion chamber, which is delimited by the cylinder and the piston either during a compression stroke in a first operating mode or during an intake stroke in a second operating mode. The control unit is designed so that for starting, fuel can be injected in a first injection directly into the combustion chamber whose respective piston is in the power stroke.

Method of controlling the charge air mass flows of an internal combustion engine including an exhaust gas turbocharger with adjustable turbine geometry

Abstract: In a method of controlling the charge air mass flow of an internal combustion engine having an exhaust gas turbocharger with adjustable turbine inlet guide vanes during dynamic operation of the engine from one stationary operating state with a given engine power output to another stationary engine operating state with a greater engine power output, the flow guide vanes are first moved to a closing position providing a minimum flow cross-section and, after a certain engine operating parameter reaches a certain control value, the guide vanes are opened at a rate depending on the charge air pressure in the intake duct of the engine to a final opening position corresponding to the other stationary engine operating state.

Method for starting motor vehicle IC engine

Abstract: The method involves using a starter (4) with a rotor (5) which is coupled directly or through gears, to the engine crankshaft (2). When, or shortly after the ignition is switched off, a controller (11) operates the starter to set the crankshaft at an angle at which the cylinder compression offers least resistance when the engine is restarted. A sensor (12) monitors the crankshaft angle. An Independent claim is included for a system for starting an IC engine.

Method of controlling a supercharged internal combustion engine and apparatus for performing the method

Abstract: In a method and apparatus for controlling a supercharged internal combustion engine including an exhaust gas turbocharger having variable turbine inlet vanes, an engine control unit includes an engine performance graph with control parameters for a multitude of engine operating points compressor performance graph is also recorded in the engine performance which represents for various exhaust gas turbocharger speeds a particular relationship between mass flow through the compressor and total pressure ratio. A multitude of engine operating curves for constant turbine guide vane positions and constant engine speeds for various engine loads and engine operating modes are also recorded and retrieved by the engine control unit for controlling the engine depending on desired engine load and engine speed for adjusting the turbine inlet vanes.

Method of operating an internal combustion engine plant

Abstract: In a method of operating an internal combustion engine particularly a motor vehicle internal combustion engine, wherein the engine is driven, during an engine start-up procedure, to a predetermined engine activation speed and fuel injection is activated, after the engine has reached the engine activation speed, only after a delay period at least one second after activation of the ignition system.

Controlled self-ignition 4-stroke engine operating process

Abstract: A method of operation of a four-stroke internal combustion engine having an intake, a combustion chamber coupled to the intake, an exhaust coupled to the combustion chamber and an exhaust recirculation device connecting the exhaust to the intake. The method includes admitting exhaust gas into the combustion chamber which is recirculated by the recirculation device from the exhaust into the intake. Thereafter, a mixture of air and fuel to be combusted is admitted through the intake into the combustion chamber which produces a stratification in the combustion chamber of the mixture of air and fuel and the exhaust gas. The stratified contents of the combustion chamber are then combusted by self-ignition.

Homogeneous charge compression ignition internal combustion engine

Abstract: A HCCI engine includes a cylinder block with a cylinder head closing off a cylinder, a power piston slidably contained within the cylinder, and a boost piston for initiating timed combustion of fuel within a combustion chamber. The boost piston is housed within a wall of the combustion chamber such that when the boost piston moves from a base position to an extended position, the heat increase within the combustion chamber is sufficient to cause fuel within the combustion chamber to ignite.

Dual fuel engine which utilizes valve lubricant as a pilot fuel

Abstract: An engine assembly includes a plenum member having an inlet opening and an outlet opening defined therein. The engine assembly further includes an air source in fluid communication with the inlet opening. The engine assembly still further includes a fuel combustion assembly having an engine block having a piston cylinder defined therein, an engine head secured to the engine block and having an intake port defined therein, and a piston which translates within the piston cylinder. The piston, the piston cylinder, and the engine head cooperate so as to define a combustion chamber. The engine assembly further includes a gaseous fuel supply valve which controls the amount of gaseous fuel advanced from a gaseous fuel source to the first intake conduit. The engine assembly still further includes an intake conduit interposed between the outlet opening and the intake port. The engine assembly still further includes a port oil injector operable to inject lubricating oil through an oil opening in the intake conduit and an intake valve positionable between an open position and a closed position. The lubricating oil lubricates the intake valve as the lubricating oil advances from the intake conduit to the combustion chamber during an intake stroke of the engine assembly, and combusts so as to ignite the mixture of natural gas and air in the combustion chamber during a compression stroke of the engine assembly. A method of operating the engine assembly is also disclosed.

Four-cycle engine having improved lubricating mechanism

Abstract: A four-cycle engine in which a mixed gas of a fuel and air containing a lubricating oil is transferred from a carburetor to a cylinder or a crank chamber, the gas is pushed out in the stage of descending the piston to the passage on the reverse side, transferred into a rocker arm chamber including an intake valve at the top of the cylinder via a passage including a valve gear mechanism, and it is directed to the cylinder in the intake stage, whereby the engine is lubricated by the lubricating oil. The engine has no oil pan and can be run at any inclination angle (360°). Also disclosed is that it is also possible for the four-cycle engine to provide a diverged second passage extending to the crank room, to provide a lead valve on a portion of the second the passage, to provide a diverged third passage extending to the lower end of the crank chamber, to provide a lead valve or rotary valve, and to provide a fourth and/or fifth passage(s) to circulate the mixed gas.

Cylinder injection system engine

Abstract: A cylinder injection system for an engine includes an injector for injecting fuel directly into a combustion chamber which is formed in the engine by a cylinder blocks, a cylinder head, and a piston. The system includes a control unit for controlling injection timing of fuel from the injector, and the control unit is configured for dividing the injection timing into several separated subtimes of injection according to the predetermined conditions of the engine.

Free piston combustion engine with electrical energy delivery e.g. for hybrid automobile, heating plant or mobile current generator

Abstract: The engine has a non-metallic permanent magnet piston (1), linearly oscillated within an engine cylinder (9) via the combustion pressure and cooperating inductive coils (12), positioned around the cylinder, providing a voltage output. Piston position sensors (9), e.g. Hall elements, controlling electromagnetic, electro-hydraulic, or electro-pneumatic engine valves.

Internal combustion engine with an exhaust gas turbocharger

Abstract: In an internal combustion engine with an exhaust gas turbocharger comprising a charge-air pipe and an exhaust gas recirculation pipe for a partial stream of the exhaust gas, a nozzle-diffuser unit is provided in the charge-air pipe, into which unit the recirculation pipe opens in a passage of restricted cross-section. In order to achieve high turbine efficiency as well as high exhaust quality, it is provided in the invention that the exhaust gas turbocharger be configured at least as a twin-entry unit, and that at least two exhaust gas flow paths be conducted separately to the entrance into the exhaust gas turbocharger, and that an exhaust gas recirculation branch depart from each exhaust gas flow path, and further that a control valve be positioned in each recirculation branch for regulation of the exhaust gas recirculation.